<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div{
            width: 150px;
            height: 150px;
            background-color: red;
            /* transition: 要过渡的属性 花费时间 运动曲线 何时开始; */
            /* 如果有多组属性用逗号隔开 */
            transition: width 1s ease ,height 1s ease,background-color 1s ease;
            /* 所以属性都是相同的变化，则可以用all */
            transition: all 1s ease;
        }
        div:hover{
            width: 400px;
            height: 400px;
            background-color: rosybrown;
        }
    </style>
</head>
<body>
    <div></div>
</body>
</html>